Apparatus for drawing-in threads of a warp through heddles in a weaving device

ABSTRACT

An apparatus for drawing-in warp threads through heddles arranged in several rows behind one another. In accordance with a program containing information about the drawing-in sequence, a selected magnet from a plurality of magnets each associated with one row of heddles is caused to grip and move a heddle from the associated row forward to the working field in which an operator may draw a thread through the heddle eye and then push the heddle aside. In response to a pulse initiated by the operator, the magnet is returned and the next heddle is moved to the working field by a different or the same magnet, as the case may be, in accordance with the program.

0 United States Patent 1 1 ,6 3,106 Fleischer 1 Apr. 4, 1972 [54] APPARATUS FOR DRAWING-IN 1,756,814 4/1930 Colman ...28/46 THREADS ()F A WARP THROUGH 2,400,342 5/1946 Drake ...28/46 2,512,165 6/1950 Meier ...28/46 HEDDLES IN A WEAVING DEVICE 2,899,736 8/1959 Fleischer ..28/46 [72] Inventor: Svend Sigurd Christie Fleischer, Klampenborg, Denmark FOREIGN PATENTS OR APPLICATIONS 7 A 2 T T I M A s s b Germany 1 ssignee z 709,424 5 1954 Great Britain ..28/46 [22] Filed: Jan. 28, 1970 Primary Examiner-James Kee Chi [21] pp NO 6 390 AttorneyBeveridge & De Grandi [57] ABSTRACT [30] Foreign Application Priority Data An apparatus for drawing-in warp threads through heddies ar- Feb. 6, 1969 Denmark ..644/69 ranged in Several rows behind one another- In accordanw with a program containing information about the drawing-in 52 us. Cl ..28/46 Sequeme, Selected magnet from a plurality of magnets each 51 1 1m. 01. ..D03j 1/14 associated with one row of heddles is caused to p and move 58 Field of Search ..28/46, 45, 44, 43 a heddle from the associated forward to the Working field in which an operator may draw a thread through the heddle 56] References Cited eye and then push the heddle aside. in response to a pulse initiated by the operator, the magnet is returned and the next N D STATES PATENTS heddle is moved to the working field by a different or the same I magnet, as the case maybe, in accordance with the program. 1,171,388 2/1916 Field ..28/46 1,645,988 10/1927 Hammer ..28/46 10 Claims, 5 Drawing Figures PATENTEDAPR 41972 3,653,106

SHEET 1 [1F 2 INVENTOR SVENID SIGURD CHRISTIE F'LE'ISCHER ATTORNEYS PATENTEDAPR 4:922 3,658,106

SHEET 2 BF 2 I N VE NTOR SVEND SIGURD CHRISTIE FLEISCHE'R APPARATUS FOR DRAWING-IN THREADS OF A WARP THROUGH HEDDLES IN A WEAVING DEVICE The present invention relates to a method of drawing-in threads of a warp through heddles in a weaving device comprising several rows of heddles.

BACKGROUND OF THE INVENTION The drawing-in of the warp threads has to take place in a specific sequence determined by the weave or texture, such as twill, linen or other weave, and the possible pattern, such as damash or jacquard pattern, of the fabric to be manufactured. It is known to facilitate the correct selection of the heddle through which a given thread is to be drawn in accordance with pre-coded information, by providing a visible marking of the associated row of heddles, e.g., by a lamp lighting up when the operator effecting the drawing-in actuates a contact. An apparatus of this kind is described in Danish Pat. No. 65,110, and by means of such an apparatus, the exacting work of counting the so-called weave design or pattern which on a pattern or point paper reproduces the desired weaving pattern, is saved, but it still is a time-consuming and awkward job to separate those heddles which are to be used from the succeeding ones in the individual rows. The known apparatus has in practice also proved somewhat difficult to work with as the signal lamps are in the way of the operator's hands when a heddle is to be separated and moved. If no apparatus is employed for marking the heddle to be moved, mistakes frequently occur and the work proceeds slowly because the operator must count his way through the rows of heddles.

SUMMARY OF THE INVENTION According to the invention there is provided a method of drawing-in threads of a warp through heddles in a weaving device containing several rows of heddles, which method comprises the steps of selecting and reaching forward a heddle intended for receiving any predetermined thread by means of a pulse-actuated magnet associated specifically with the row of heddles in question, and controlling the movement of said magnet by means of a predetermined code.

The method has the important advantage that there is not only a marking of the correct row of heddles prior to each drawing-in, like in the prior art, but the correct heddle is taken direct from its row and passed forward to the operator, who

thus only has to take the thread, draw it through the eye of the heddle and push the heddle aside towards the heddles previously drawn-in. The work is hereby facilitated to a considerable degree and may consequently be carried out more quickly than heretofore, while at the same time it has been ensured that the drawing-in always takes place in the correct sequence of the heddles, without requiring any particular attention on the part of the operator.

The invention also provides an apparatus for drawing-in threads of a warp through heddles in a weaving device containing several rows of heddles, said apparatus comprising a frame structure having means for mounting support means for a plurality of weaving shafts behind one another, each weaving shaft including support means and a row of said heddles slidingly supported by said heddle support means; a gripper unit associated with each weaving shaft and having a gripper including a magnetic gripper head, means for moving said gripper between two end positions thereof; a common holder mounted outside said weaving shafts and including means for mounting all said gripper units thereon with the gripper heads thereof entending inwardly between adjacent weaving shafts; information carrier means containing coded information about a desired sequence of drawing-in operations; pulse-actuated drive means for intermittently advancing said information carrier means; means for reading-out said coded information and control means associated with said read-out means and said gripper drive means for actuating said drive means in accordance with the information read-out.

Each gripper may comprise an arm which is pivotally supported in a frame mounted on the common holder which frame is adjustable in the transverse direction of the shafts. It is then possible to adjust the grippers operating between the shafts according to the thickness of the shafts, so that irrespective of their possibly varying thickness they can always be spaced as closely as possible. Because the number of shafts may be very high in practice weaving is carried out with as many as 32 shafts this evidently is of importance for the operation of the apparatus, during which the operator has to reach in between all the shafts in order to take hold of the warp threads.

The pivot center of the gripper may be situated in such a way that during the first part of its movement it raises the beddle held by the gripper head. Hereby it is ensured that while moving, the selected heddle does not rest on the carrying rails of the shaft, which might render the shifting of the heddle difficult.

On account of the limited space between the shafts, the gripper head may be secured detachably on the gripper arm. It is then possible to employ wider and hence more powerful magnets than if the gripper heads would have to be introduced from the outside between the closely-spaced frame members of the shafts.

The holder may comprise a carriage having a substantially flat vertical body and three travelling wheels on rollers, of which two travel on a support rail situated at one long side of the apparatus, while the third is in lateral contact with a second support rail extending parallel to the first support rail. This ensures a compact construction of the carriage which takes up only relatively little space at one long side of the apparatus.

The driving means of each gripper may comprise a pulling cord which, at one end, is fastened to the apparatus and from there extends over a first pin or roll coaxial with the pivot center of the gripper arm and further over a pin or roll secured to the gripper arm at a distance from said pivot center to a spring-loaded pulling member controlled by the read-out means. This provides an extremely simple and reliable driving mechanism requiring very little space which, in view of the above-mentioned conditions prevailing when threads are to be drawn through heddles in a great number of shafts, is particularly valuable. The prescribed path of the pulling cord has, moreover, the advantage that to all intents and purposes, there is no relative movement between the cord and the pins on the gripper arms and consequently very little wear on the cord.

Each pulling member may comprise a pivotal lever which is spring-loaded against a rotary cam controlled by the pulsecontrol means and which interacts with a locking pawl controlled by the read-out means so that, in its locking position, the pawl stops the movement of the lever towards the cam. All locking pawls except the one associated with the selected weaving shaft, will then block the corresponding pivotal lever, so that only the lever associated with the selected shaft is able to follow the rotation of the cam under the action of the spring load and consequently to tighten the associated pulling cord and pivot the gripper arm together with the heddle gripped by the magnet on the arm.

When the information carrier comprises a punched strip, each locking pawl may be mounted on a second pivotal lever which constitutes the read-out means of the associated weaving shaft, and which may be engaged with the associated perforation position in the strip and disengaged therefrom by means of a further rotary cam controlled by the pulse control means. All of the said cam means be secured to a common shaft driven by a stepping motor.

Further features and advantages of the invention will become apparent from the following description in which reference is made to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a lateral view of the apparatus,

FIG. 2 shows an end view of the apparatus shown in FIG. 1, seen from the lefthand end,

FIG. 3 is a fractional view on a larger scale of the apparatus as shown in FIG. 1,

FIG. 4 is another fractional view on an even larger scale illustrating the longitudinally displaceable carriage with a single gripper means as well as the control mechanisms of the apparatus, and

FIG. 5 is a perspective view on a still larger scale illustrating a gripper in action.

In FIGS. 1-3 several parts of the apparatus have been omitted for the sake of clarity.

DESCRIPTION OF PREFERRED EMBODIMENT The apparatus illustrated in the drawing includes a frame structure comprising two end frames 1, which rest on the floor by means of feet 2 and which, in addition, have supporting legs 3. The frames are connected by means of upper and lower horizontal rails 4 and 5 which at the same time serve as support and guide rails for a carriage 6 dealt with below.

Furthermore, at its two ends, the frame structure carries projecting posts 7 which, for the sake of clearness, are only shown in FIG. 2 and to which in turn are secured horizontal transverse carrying bars 8 intended for the suspension of a plurality of weaving shafts 9. For the sake of clearness, in FIG. 2 only seven weaving shafts are shown, but it will be appreciated that the carrying bars 8 or other corresponding means for the mounting of weaving shafts are normally designed to accommodate a larger number of shafts. These carrying means are not shown in detail, since their design as such forms no part of the present invention.

Each weaving shaft 9 consists in a manner known per se of a frame having an upper and a lower frame beam 10 and 11, respectively, which at their ends are connected by vertical frame members 12. Each shaft frame comprises an upper carrying rail 13 and a lower carrying rail 14, on which the heddles 15 of the shaft are guided by means of oblong eyes, vide also FIG. 5. Each heddle 15 may, in a known manner, be made of thin steel sheet or of steel wire and approximately at the center ofits length it has an eye 16, vide FIG. 3.

The warp threads that are to be drawn through the eyes 16 of the individual heddles in a pre-determined sequence, are shown in FIG. 2 as being wound around a beam 17 which is mounted in a frame 18 placed behind the apparatus. The individual warp threads are arranged in a pre-determined sequence and are temporarily held in this sequence, e.g., as indicated in FIG. 2 by means of a so-called clip 19 which is mounted on the frame of the apparatus. Instead of the clip shown, any other suitable means may be employed for holding the threads in the correct sequence, for instance, the selector seam described in Danish Pat. specification No. 61,805, or the warp threads may be advanced in sequence by a reaching-in machine.

The carriage 6, which is seen in greater detail in FIG. 4, comprises a substantially flat vertical beam 20, which may have suitable bracings (not shown) and which, in lateral view, is T-shaped. The topmost horizontal part of the beam 20 carries at its extremities two rotatably supported rollers 21 which support the carriage on the rail 4 and permit the travel of the carriage along the rail. At the bottom, the beam 20 carries a supporting roller 22 which is rotatably supported about a vertical axis in the beam and which, from the side, engages the supporting rail 5. To the topmost horizontal leg of the beam 20, there are secured two transverse carrying bars 23, which extend below the weaving shafts 9 suspended on the frame structure.

For each weaving shaft 9 there is provided a gripper mechanism comprising a frame, in which a gripper arm is pivotably joumalled. Each frame consists of two perpendicular side members 24, which are connected by means of two parallel thin side plates 25, between which the arm 26 is journalled. The two side members 24 have bores, through which the carrying bars 23 extend with a relatively tight fit, which permits a transverse adjustment of the frames on the carrying bars.

Each gripper arm 26 carries at its upper end a magnetic gripper head 27 which, in the embodiment shown, comprises two permanent magnets 28 which are secured, one above the other, to the gripper head 27 with their poles facing in the iongitudinal direction of the weaving shaft 9. The gripper head 27 may be detachably secured, e.g., by means of a guide-way, not shown more detailed, on the end of the gripper arm 26 which is thin as measured transversely of the weaving shafts. An actuating arm 29 may be secured to the free end of the gripper arm 26, as shown in FIGS. 3 and 4, so that the gripper arm may be manually pressed away sideways from a heddle 15 held by the magnets, whereby the heddle is released. For this purpose the arm 26 itself might alternatively be provided with a projection which, during the pivoting of the arm, interacts with another projection on the frame 24, 25.

The pivoting of the arm 26 with the magnetic head 27 discussed above is efiected with the aid of the driving means described below. These means comprise for each arm a pulling cord 30 which, at its left-hand end as shown in FIG. 1 is secured to the frame structure of the apparatus. The cord 30 is led around a pin 31 coaxial with the pivotal axis of the arm 26 and from there around a pin 32 mounted on the lowermost end of the arm. From there, the cord extends to the actuating mechanism diagrammatically indicated in FIGS. 1 and 4, which is mounted at one end of the apparatus.

The actuating mechanism comprises for each pulling cord 30 and hence for each weaving shaft 9 a first bell crank lever 33 having a leg 33a, to the free end of which the cord 30 is fixed. The lever 33 can pivot around the axis of a pin 34 and its other leg 33b carries a follower roll 35, which is kept in contact with a cam disc 36 by means of a tension spring 37.

A second bell crank lever 38 cooperates with each lever 33, and the lever 38 is pivotable around the axis of a pin 39. One leg 38a of each lever 38 engages a roll 40, which is secured to the same shaft 41 as the cam disc 36 and thus rotates synchronously with same. The other, substantially horizontal leg 38b of each lever 38 is, at its free end, bent down to form a downwardly-facing sensing pin 42. The sensing pins 42 interact with a perforated paper strip 43 which is led around a rotatably supported drum 44. The strip 43 is guided with respect to the drum and advanced via the drum in a known manner by continuous perforations not shown at its edges and interacting teeth on the drum 44. The drum is advanced step by step by means of a pawl mechanism comprising pawl teeth 45 on the drum and a pawl 46 mounted on a bell crank lever 47 pivotable around the axis of pin 34. The lever 47 is controlled by a cam 48 secured to the shaft 41, and is held against the cam by means of a spring 49. The pawl mechanism may be provided at one end or at both ends of the drum, depending upon the width of the drum.

The paper strip 43 serves as the carrier of information relating to the sequence of the heddles, or to be more exact, the associated shafts 9, through which warp threads from the beam 17 are to be drawn successively. In the embodiment shown, this information is present in the form of perforations or holes in a plurality of parallel rows running longitudinally of the strip 43. The distance between adjacent rows of holes as measured in the lateral direction of the strip corresponds to the distance between the sensing pins 42 of adjacent levers 38. In the longitudinal direction of the strip 43 the spacing between adjacent holes in each row corresponds to the pitch determined by the pawl mechanism 45, 46, and for each position of the drum 44 there is only one hole in the lateral row of hole positions across the strip corresponding to a specific weaving shaft. The corresponding pin 42 will consequently be able to drop into this hole, while the other pins 42 rest on the top side of the strip. In order to obtain a suitably ample travel of the pin 42, and hence the lever 38, rows of holes 50 have been drilled into the surface of the drum 44 with a pitch which corresponds to the advancing or feeding step of the drum as determined by the pawl mechanism 45, 46.

Each lever 38 carries on the top side of its horizontal leg 38b a projection 51, which may interact with a locking pawl 52 secured to the vertical leg 33a of the associated lever 33. The parts 51 and 52 are constructed and arranged in such a way that the pawl 52 is stopped by the projection 51 when the lever 38 is in the raised position, i.e., when its pin 42 has not dropped through a hole in the strip 43. Since in such a case the lever 33 is prevented from swivelling clockwise as seen in FIG. 4, no pull can be exerted in the associated cord 30 either.

The said swivelling of the levers 33 is effect by means of the cam discs 36 mounted on the shaft 41, which shaft performs one revolution for every time the operator initiates a pulse, e.g., through a pedal, not shown, or a contact incorporated in a heddle hook, by means of which a warp thread is drawn through the eye of a heddle. The one revolution of the shaft 41 mentioned may be carried into effect in any suitable manner, e.g., by means of a so-called stepping motor or by the employment of a clutch, known per se, between the electric motor and the shaft, which clutch is automatically released after one revolution of the shaft, 5

In the normal or inoperative position of the shaft 41, the flat portion of each cam disc 36 shown in FIG. 4 faces the associated roll 35, and the springs 37 will consequently tend to pivot all levers 33 clockwise, but as mentioned above, this is only possible as far as one lever is concerned, i.e., the lever where the pin 42 on the associated lever 38 engages in a hole in the strip 43. The other levers 33 are held by the associated locking pawls 52 in the position shown, FIG. 4, so that the gripper arm 26 associated with each of the levers 33 lies against the first heddle in that group of heddles to the right of the actual working area. Only that gripper arm, the pulling cord 30 of which has been tightened has been swivelled to the position shown in FIG. 3, in which the magnets 28 of the gripper head hold a selected heddle in the working area for the drawing-in of a warp thread.

When the drawing-in operation is concluded, the operator presses the arm 29, whereby the gripper arm 26 is pressed to the rear and the heddle 15 is now free, so that it may be pushed manually to the left to join the bundle of heddles in the shaft in question, through which warp threads have been drawn earlier. By actuating the above-mentioned contact, the operator now starts the shaft 41, which performs one clockwise revolution during which first the above mentioned one roll 35 is actuated which, by means of its spring 37, was kept in contact with the associated cam disc 36. The as sociated lever 33 consequently pivots counter-clockwise, whereby the gripper arm 26 that was operative at the preceding drawing-in operation, swivels back into the position shown in FIG. 4 and comes to rest against the next heddle in the weaving shaft in question.

Thereupon all the levers 38 are actuated by the associated rolls 40 whereby they are lifted clear of the perforated strip 43, including that lever, the pin 42 of which engaged with a hole in the strip. When all the levers 38 are thus clear of the strip 43, the pawl mechanism 45, 46 is actuated by the cam 48 and the drum 44 is rotated one step forward to the next position. During the continued rotation of shaft 41, all levers 38 remain in a raised position except one, namely the lever, the pin 42 of which is now able to drop into the next hole in the strip 43.

During the last part of the rotation of the shaft 41, all the rolls 35 will tend to follow their cam discs 36 and thereby swivel the levers 33 clockwise, but this is only possible for the lever associated with that lever 38 of which the pin 42 engages in a hole in the strip 43, so that the lever 38 has dropped. All the other levers 33 are locked by the engagement between the associated projections 51 and locking pawls 52. The result will therefore be that only one of the gripper arms 26 swivels into the position shown in FIG. 3 and carries along a heddle from the associated weaving shaft. The next warp thread may now be drawn through the eye 16 of this heddle and the operation thereupon continues as described.

When the gripper arm, as explained above, carries out a swivel or pivot movement, during which it passes through the vertical position, while there is no positive control of the movement, provision will have to be made for the automatic return swivelling of the arm, e.g., by means of a spring associated with the arm. The grippers shown in the drawing which grip or engage each heddle close to its lowermost end, may be supplemented with grippers mounted in the upper part of the apparatus for interaction with the uppermost end of the heddles. The actuating of the grippers may, as intimated, also take place in other ways, by way of example with the aid of electromagnets which, however, will normally require substantially more space than the described, purely mechanical driving means, particularly if they are to be designed so that an actuated gripper is returned into its resting position only in response to a subsequent pulse.

It is possible to supplement the apparatus according to the invention with light sources, known per se, for marking the selected heddle or for marking the warp layer from which a warp thread is to be removed, in case warp threads are taken from more than one layer, e.g., from two beams, according to a pre-determined program. The information coded in advance and concerning the sequence of heddles may be stored in any suitable form and the read-out may take place entirely or partly electrically. When using a perforated strip, it might also be possible, instead of having one hole in each transverse row, as described, to have holes in all the hole positions with the exception of the one which corresponds to the gripper that is to be activated. In particular with more simple weaving patterns, it would be possible to employ cam discs instead of punched strips or perforated tape and inter alia in that case a hydraulic or pneumatic actuation of the grippers could be used. In the embodiment described, the movement of the carriage, on which the gripper units are mounted, takes place manually and would be performed at suitable intervals when a certain number of heddles have been provided with warp threads; it would, however, also be possible to employ a purely mechanical advance of the carriage. To improve the versatility of the apparatus it may be advantageous to design the supporting means of the carriage in such a way that it may be raised or lowered in order to obtain the most favorable operating position in relation to the heddles of the shafts. It is expedient to construct the read-out mechanism in such a way that the movement of the pulse carrier may be reversed, for instance, if a fault in the drawing-in should be noted, so that it is necessary to return to the place where the fault occurred. In order to fix or locate the individual shaft frames and the frames of the gripper units, it is possible to employ spacers between the individual frames. The apparatus may be provided with wheels instead of the fixed feet shown, and the apparatus may also form a part of a larger textile machine; it may, for example, be combined with a reaching-in machine or with a machine which also feeds warp etectors. Even if it is not shown in the drawing, it is implied that between the frame beams of the shafts and the heddle carrying rails, there will frequently be provided supporting hooks, which periodically have to be moved sideways and this may expediently take place together with the above-described manual moving of the carriage.

Among other modifications of the apparatus, which are not shown, the following may be mentioned. Instead of the pins shown on the gripper arms, which guide the pulling cord, closed eyelets may be used. Instead of the gripper arm supporting frame comprising two side members and two side plates, it would be possible to use a frame made of a single plate with, e.g., welded-on hubs for the bores receiving the transverse carrying bars. In the plate there may be two wholly or substantially horizontal slits, between which the plate is cranked, so that the flat gripper arm passes through the slits and extends alternately on one and the other side of the plate. It is important in both this and the embodiment described that in the transverse direction the frame acts as a spacing means which ensures that the gripper arm is able to swivel without being impeded by the shafts. This is of special importance in certain shaft frames which carry so-called guide pieces that are somewhat thicker than the shaft frame itself and which could impede the free movement of the gripper arm, if the arm was not protected by its frame. In cases, in which the number of weaving shafts is less than the maximum, it is possible to swivel the inoperative grippers away together with their associated frames, so that they are only supported by one horizontal carrying bar and do not interfere with the functioning of the operative grippers. instead of the holes in the guide drum of the control strip shown in the drawing, into which the sensing pins are able to drop, it would be possible to have continuous axial slots in the surface of the drum. All the pulse-actuated grippers might be mounted at the top edge of the weaving shafts so that the heddles would be gripped at their topmost ends. The pulse for actuating the selected gripper could be produced by the closing of a contact which is actuated when the gripper arm is moved somewhat beyond its normal extreme position subsequent to the conclusion of a separating operation, for instance, by means of the actuating arm shown in FIG. 4. Even if the elements serving to support the weaving shafts are described as a part of the apparatus in the embodiment shown, these means may be separate, since frequently a weaving mill has such means for suspending weaving shafts, and in that case the separating apparatus may be constructed and arranged so that the said existing means may simply be mounted on the frame of the apparatus.

What I claim is:

1. Apparatus for drawing-in threads of a warp through heddles in a weaving device containing a plurality of parallel weaving shafts, each weaving shaft including heddle support means and a row of heddles slidingly supported by said heddle support means, comprising:

a frame structure having means for mounting said plurality of weaving shafts one behind the other;

a plurality of gripper units, each unit being associated with one of said weaving shafts and each unit having a frame, an arm supported in said frame and movable relative thereto in a plane parallel to the plane of said plurality of weaving shafts, a magnetic gripper head detachably secured to said arm, and drive means for moving said gripper arm and head between two end positions thereof;

a common holder mounted outside said weaving shafts and including means for mounting all said gripper units thereon with the gripper arms and heads thereof extending vertically inwardly between adjacent weaving shafts;

information carrier means containing coded information about a desired sequence of drawing-in operations,

pulse-actuated drive means for intermittently advancing said information carrier means,

means for reading-out coded information and control means responsive to said read-out means for selectively actuating said plurality of drive means in accordance with the information read-out.

2. Apparatus as claimed in claim 1, wherein said gripper arm is pivotal about an axis which is positioned so that during the first part of the gripper movement, a heddle held by a gripper head is raised with respect to the heddle support means.

3. Apparatus as claimed in claim 1 further comprising an actuating member secured to each gripper arm for manually displacing said arm transversely of the plane of said weaving shafts.

4. Apparatus as claimed in claim 1, wherein the means for mounting said gripper units on said holder comprises two supporting bars on said holder extending transversely of said weaving shafts, and two matching apertures in each of said frames.

5. Apparatus as claimed in claim 1, wherein said frame structure comprises a first horizontal support rail extending parallel to said weaving shafts and a second horizontal support rail extending parallel thereto at a lower location, and said common holder comprises a carriage having a substantially flat vertical body, two rollers supported on said body for rotation about a horizontal axis and engaging said first horizontal support rail from above, and one roller supported on said body for rotation about a vertical axis and engaging said second horizontal support rail from one side thereof.

6. Apparatus as claimed in claim 1, wherein said gripper unit mounting means are constructed and arranged so that each gripper head engages a heddle from a weaving shaft adjacent one end of said heddle.

7. Apparatus as claimed in claim 2, wherein said gripper drive means includes for each gripper unit a cord secured at one end to said frame structure, a first roll on said gripper unit frame coaxial with the pivotal axis of said gripper arm, a second roll on said arm and spaced from said first roll, said cord extending in succession over said first and second rolls, a pulling member controlled by said read-out means and connected to the other end of said cord, and a spring means acting upon said pulling member to pull said cord tight.

8. Apparatus as claimed in claim 7, wherein said pulling member comprises a pivotal lever, and said gripper drive means further includes a rotary cam controlled by said pulseactuated drive means, spring means biasing said lever towards said cam, a first locking pawl on said pivotal lever and a second locking pawl controlled by said read-out means, said pawls cooperating to prevent said lever from following the movement of said cam.

9. Apparatus as claimed in claim 8, wherein said information carrier means comprises a punched strip and said readout means comprises a second pivotal lever, said second locking pawl being secured to said second lever, and a second rotary cam controlled by said pulse-actuated drive means and arranged to engage and disengage said second lever into and from the perforations of said punched strip.

10. Apparatus as claimed in claim 8, wherein said first and second cams are secured to a common shaft, and said drive means includes a stepping motor operatively connected to rotate said shaft. 

1. Apparatus for drawing-in threads of a warp through heddles in a weaving device containing a plurality of parallel weaving shafts, each weaving shaft including heddle support means and a row of heddleS slidingly supported by said heddle support means, comprising: a frame structure having means for mounting said plurality of weaving shafts one behind the other; a plurality of gripper units, each unit being associated with one of said weaving shafts and each unit having a frame, an arm supported in said frame and movable relative thereto in a plane parallel to the plane of said plurality of weaving shafts, a magnetic gripper head detachably secured to said arm, and drive means for moving said gripper arm and head between two end positions thereof; a common holder mounted outside said weaving shafts and including means for mounting all said gripper units thereon with the gripper arms and heads thereof extending vertically inwardly between adjacent weaving shafts; information carrier means containing coded information about a desired sequence of drawing-in operations, pulse-actuated drive means for intermittently advancing said information carrier means, means for reading-out coded information and control means responsive to said read-out means for selectively actuating said plurality of drive means in accordance with the information read-out.
 2. Apparatus as claimed in claim 1, wherein said gripper arm is pivotal about an axis which is positioned so that during the first part of the gripper movement, a heddle held by a gripper head is raised with respect to the heddle support means.
 3. Apparatus as claimed in claim 1 further comprising an actuating member secured to each gripper arm for manually displacing said arm transversely of the plane of said weaving shafts.
 4. Apparatus as claimed in claim 1, wherein the means for mounting said gripper units on said holder comprises two supporting bars on said holder extending transversely of said weaving shafts, and two matching apertures in each of said frames.
 5. Apparatus as claimed in claim 1, wherein said frame structure comprises a first horizontal support rail extending parallel to said weaving shafts and a second horizontal support rail extending parallel thereto at a lower location, and said common holder comprises a carriage having a substantially flat vertical body, two rollers supported on said body for rotation about a horizontal axis and engaging said first horizontal support rail from above, and one roller supported on said body for rotation about a vertical axis and engaging said second horizontal support rail from one side thereof.
 6. Apparatus as claimed in claim 1, wherein said gripper unit mounting means are constructed and arranged so that each gripper head engages a heddle from a weaving shaft adjacent one end of said heddle.
 7. Apparatus as claimed in claim 2, wherein said gripper drive means includes for each gripper unit a cord secured at one end to said frame structure, a first roll on said gripper unit frame coaxial with the pivotal axis of said gripper arm, a second roll on said arm and spaced from said first roll, said cord extending in succession over said first and second rolls, a pulling member controlled by said read-out means and connected to the other end of said cord, and a spring means acting upon said pulling member to pull said cord tight.
 8. Apparatus as claimed in claim 7, wherein said pulling member comprises a pivotal lever, and said gripper drive means further includes a rotary cam controlled by said pulse-actuated drive means, spring means biasing said lever towards said cam, a first locking pawl on said pivotal lever and a second locking pawl controlled by said read-out means, said pawls cooperating to prevent said lever from following the movement of said cam.
 9. Apparatus as claimed in claim 8, wherein said information carrier means comprises a punched strip and said read-out means comprises a second pivotal lever, said second locking pawl being secured to said second lever, and a second rotary cam controlled by said pulse-actuated drive means and arranged to engage and disengage said second lever into and from the perforations of said punChed strip.
 10. Apparatus as claimed in claim 8, wherein said first and second cams are secured to a common shaft, and said drive means includes a stepping motor operatively connected to rotate said shaft. 